1)Size:M3 to M12 2)Flat head, flat hexagon head,small countersunk head 3)Material:mild steel,SUS304 Feature:1) Size of rivet nuts: M3 to M122) Flat head, flat hexagon head, small countersunk head3) Material: mild steel, SUS3044) The best way of sheet metal connectingOuter packing: Carton or poly bag + Palletour company supply rivet nuts,nuts,fastener. Rivet nut